Frictional lock-nut for bolts.



No. 838,948. PATENTED DEC. 18, 1906.

G. BRYAR. P'RIGTIONAL LOCK NUT FOR BOLTS.

APPLICATION TILED FEB.1Z, 1906.

UNITED STATES PATENT OFFICE.

GEORGEBRYA R, OF BOSTON, MASSACHUSETTS, ASSIGNOR, BY DIRECT AND MESNEASSIGNMENTS, OF SEVEN-EIGHTHS TO JOHN M. SMITH, OF ST.

JOHNS, CANADA.

Specification of Letters Patent.

Patented Dec. 18, 1906.

Application filed February 12, 1906. Serial No. 300.786.

To all whom, it may concern:

Be it known that I, GEORGE BRYAR, a citizen of the United States, and aresident of Boston, county of Suffolk, and State of Massachusetts, haveinvented certain new and useful Im rove'ments in Frictional Lock- Nutsfor Sblts, of which the following is a specification, reference beinghad to the drawings accompanying the same.

My invention relates to lock-nuts for bolts wherein the nut is so formedas to produce a holding friction between the threads of the nut and thethreads of the bolt sufficient to prevent the nut from becoming loose byshock or jar of the structure in which the bolt is mounted.

The object of my invention is to so construct a nut for a bolt that itsthreads will have sufficient frictional grip upon the threads of thebolt to prevent its becoming loose and without producing sulficientfriction to result in abrasion of the threads on the bolt and nut.

In the drawings accompanying this specification, Figure 1 represents abolt having my frictional lock-nut mounted thereon. Fig. 2 is asectional plan view of a nut and the bolt to which it is attached. Fig.3 represents a plan View of my improved locknut removed from the boltand shows the manner in which the body portion is bent inward to producethe frictional grip. Fig. 4 is a side elevation of a modified form ofnut, showing the part bent inward to produce a frictional grip.

Referring to the drawings, 1 denotes a bolt which is threaded at oneend, and 2 denotes the improved lock nut. This improved lock-nut isformed by slitting a nut transversely to its center, or thereabout, toform a slit 3 and also preferably by slitting the same longitudinally,as at 4, inward from the outer face of the nut to the slit 3, said slitit being formed at one end of the slit 3. The nut 2 is tapped orinternally threaded previous to being slitted, and by thus cutting orslitting the nut as just described a loose wing or finger 5 6 is formed.The free end of the said wing or finger is then slightly bent inwardradially, as shown in Fig. 3, to cause the same to bind on the threadedportion of a bolt radially, and the free end of the I said wing orfinger is also slightly bent inward longitudinally of the nut and bolt,as shown in Fig. 4, so as to bring the threads on the free threadedportion of said wing or finger somewhat out of register With the threadson the adjacent threaded portion of said nut, and thus cause the saidfinger to frictionally engage the threads of the bolt in the directionof the length of the latter, as well as radially of the bolt, so as tofirmly grip the same, and thereby prevent the nut from working loose bythe combined gripping effect resulting from the radial displacement ofthe free end of said finger, as also by the displacement thereoflongitudinally of the nut and the bolt.

The wing or finger formed by slitting the nut transversely and bentinward longitudinally of the nut, as SllOWll and described, will besomewhat inclined, so that while the internal threads at the base orconnected end of the said wing or finger will be in register with theadjacent communicating parts of the threads the displaced portion willbe so inclined that when the nut is screwed into place on the bolt thedisplaced wing or finger, while still gripping the threaded portion ofthe bolt strongly, will be forced to resume or nearly resume itsoriginal or normal position, as will be understood from Fig. 1, while atthe same time this displaced portion of the wing or finger will grip thebolt with sufiicient force to effectively lock the nut and preventaccidental displacement thereof. This gripping effect will, however, notbe so great as to prevent the nut from being readily screwed into placeby a suitable wrenchv Owing to the considerable length of the wing orfinger 5 6, it will have sufficient elastieity, so that the nut may beused repeatedly, if necessary, as when the nut is removed from the boltthe gripping wing or finger will resume nearly or quite its originaldisplaced position, as shown in Figs. 3 and 4.

Having thus described my invention, I claim and desire to secure byLetters Patent A frictional lock-nut having an internallythreaded hole,a transverse slit and a longitudinal slit extending from one end of saidnut to said transverse slit, at one end of the latter, said slitsforminga wing or finger, and

said wing or finger being slightly bent inward radially and being alsobent inward toward said transverse slit longitudinally of the nut,

In testimony whereof I have hereunto set my hand, in the presence of twosubscribing 10 i Witnesses, this the 24th day ofJanuary, A. D.

thereby displacing a portion of said inter- 1.)06. V nally-threadedfinger, both radially and lon- GEORGE BR YAR. gitudinally of the nut, toafford a radial and l \Vitnesses:

longitudinal frictional grip on a threaded. por- R. P. ELLIOTT, tion ofa bolt.

H. M. KELSO.

